Merge time(keeping) updates from John Stultz:
"Just a small set of changes, the biggest changes being the MONOTONIC_RAW
handling cleanup, and a new kselftest from Miroslav. Also a a clear
warning deprecating CONFIG_GENERIC_TIME_VSYSCALL_OLD, which affects ppc
and ia64."
Pull clockevent changes from Daniel Lezcano:
- Factored out moxart, aspeed, cortina drivers into a generic timer fttrm010.
Take the opportunity to add the delay timer (Linus Walleij)
- Saved / restored tcb atmel context at suspend/resume (Alexandre Belloni)
- Added ast2500 compatible string and fixed aspeed2500 initialization (Daniel
Lezcano)
- Added clock names property for aspeed (Andrew Jeffery)
- Renamed clocksource_of to timer_of (Daniel Lezcano)
- Added a common timer init routine (Daniel Lezcano)
Due to how the MONOTONIC_RAW accumulation logic was handled,
there is the potential for a 1ns discontinuity when we do
accumulations. This small discontinuity has for the most part
gone un-noticed, but since ARM64 enabled CLOCK_MONOTONIC_RAW
in their vDSO clock_gettime implementation, we've seen failures
with the inconsistency-check test in kselftest.
This patch addresses the issue by using the same sub-ns
accumulation handling that CLOCK_MONOTONIC uses, which avoids
the issue for in-kernel users.
Since the ARM64 vDSO implementation has its own clock_gettime
calculation logic, this patch reduces the frequency of errors,
but failures are still seen. The ARM64 vDSO will need to be
updated to include the sub-nanosecond xtime_nsec values in its
calculation for this issue to be completely fixed.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: "stable #4 . 8+" <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In tests, which excercise switching of clocksources, a NULL
pointer dereference can be observed on AMR64 platforms in the
clocksource read() function:
u64 clocksource_mmio_readl_down(struct clocksource *c)
{
return ~(u64)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
}
This is called from the core timekeeping code via:
cycle_now = tkr->read(tkr->clock);
tkr->read is the cached tkr->clock->read() function pointer.
When the clocksource is changed then tkr->clock and tkr->read
are updated sequentially. The code above results in a sequential
load operation of tkr->read and tkr->clock as well.
If the store to tkr->clock hits between the loads of tkr->read
and tkr->clock, then the old read() function is called with the
new clock pointer. As a consequence the read() function
dereferences a different data structure and the resulting 'reg'
pointer can point anywhere including NULL.
This problem was introduced when the timekeeping code was
switched over to use struct tk_read_base. Before that, it was
theoretically possible as well when the compiler decided to
reload clock in the code sequence:
now = tk->clock->read(tk->clock);
Add a helper function which avoids the issue by reading
tk_read_base->clock once into a local variable clk and then issue
the read function via clk->read(clk). This guarantees that the
read() function always gets the proper clocksource pointer handed
in.
Since there is now no use for the tkr.read pointer, this patch
also removes it, and to address stopping the fast timekeeper
during suspend/resume, it introduces a dummy clocksource to use
rather then just a dummy read function.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: stable <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Daniel Mentz <danielmentz@google.com>
Link: http://lkml.kernel.org/r/1496965462-20003-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.
This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.
Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.
One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications. For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).
Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.
Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull configfs updates from Christoph Hellwig:
"A fix from Nic for a race seen in production (including a stable tag).
And while I'm sending you this I'm also sneaking in a trivial new
helper from Bart so that we don't need inter-tree dependencies for the
next merge window"
* tag 'configfs-for-4.12' of git://git.infradead.org/users/hch/configfs:
configfs: Introduce config_item_get_unless_zero()
configfs: Fix race between create_link and configfs_rmdir
Pull block layer fix from Jens Axboe:
"Just a single fix this week, fixing a regression introduced in this
release.
When we put the final reference to the queue, we may need to block.
Ensure that we can safely do so. From Bart"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: Fix a blk_exit_rl() regression
Pull dmi fixes from Jean Delvare.
* 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
firmware: dmi_scan: Check DMI structure length
firmware: dmi: Fix permissions of product_family
firmware: dmi_scan: Make dmi_walk and dmi_walk_early return real error codes
firmware: dmi_scan: Look for SMBIOS 3 entry point first
Currently they return -1 on error, which will confuse callers if
they try to interpret it as a normal negative error code.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Pull networking fixes from David Miller:
1) The netlink attribute passed in to dev_set_alias() is not
necessarily NULL terminated, don't use strlcpy() on it. From
Alexander Potapenko.
2) Fix implementation of atomics in arm64 bpf JIT, from Daniel
Borkmann.
3) Correct the release of netdevs and driver private data in certain
circumstances.
4) Sanitize netlink message length properly in decnet, from Mateusz
Jurczyk.
5) Don't leak kernel data in rtnl_fill_vfinfo() netlink blobs. From
Yuval Mintz.
6) Hash secret is never initialized in ipv6 ILA translation code, from
Arnd Bergmann. I guess those clang warnings about unused inline
functions are useful for something!
7) Fix endian selection in bpf_endian.h, from Daniel Borkmann.
8) Sanitize sockaddr length before dereferncing any fields in AF_UNIX
and CAIF. From Mateusz Jurczyk.
9) Fix timestamping for GMAC3 chips in stmmac driver, from Mario
Molitor.
10) Do not leak netdev on dev_alloc_name() errors in mac80211, from
Johannes Berg.
11) Fix locking in sctp_for_each_endpoint(), from Xin Long.
12) Fix wrong memset size on 32-bit in snmp6, from Christian Perle.
13) Fix use after free in ip_mc_clear_src(), from WANG Cong.
14) Fix regressions caused by ICMP rate limiting changes in 4.11, from
Jesper Dangaard Brouer.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (91 commits)
i40e: Fix a sleep-in-atomic bug
net: don't global ICMP rate limit packets originating from loopback
net/act_pedit: fix an error code
net: update undefined ->ndo_change_mtu() comment
net_sched: move tcf_lock down after gen_replace_estimator()
caif: Add sockaddr length check before accessing sa_family in connect handler
qed: fix dump of context data
qmi_wwan: new Telewell and Sierra device IDs
net: phy: Fix MDIO_THUNDER dependencies
netconsole: Remove duplicate "netconsole: " logging prefix
igmp: acquire pmc lock for ip_mc_clear_src()
r8152: give the device version
net: rps: fix uninitialized symbol warning
mac80211: don't send SMPS action frame in AP mode when not needed
mac80211/wpa: use constant time memory comparison for MACs
mac80211: set bss_info data before configuring the channel
mac80211: remove 5/10 MHz rate code from station MLME
mac80211: Fix incorrect condition when checking rx timestamp
mac80211: don't look at the PM bit of BAR frames
i40e: fix handling of HW ATR eviction
...
Pull ACPI fixes from Rafael Wysocki:
"These revert an ACPICA commit from the 4.11 cycle that causes problems
to happen on some systems and add a protection against possible kernel
crashes due to table reference counter imbalance.
Specifics:
- Revert a 4.11 ACPICA change that made assumptions which are not
satisfied on some systems and caused the enumeration of resources
to fail on them (Rafael Wysocki).
- Add a mechanism to prevent tables from being unmapped prematurely
due to reference counter overflows (Lv Zheng)"
* tag 'acpi-4.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPICA: Tables: Mechanism to handle late stage acpi_get_table() imbalance
Revert "ACPICA: Disassembler: Enhance resource descriptor detection"
Pull media fixes from Mauro Carvalho Chehab:
- some build dependency issues at CEC core with randconfigs
- fix an off by one error at vb2
- a race fix at cec core
- driver fixes at tc358743, sir_ir and rainshadow-cec
* tag 'media/v4.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] media/cec.h: use IS_REACHABLE instead of IS_ENABLED
[media] cec: race fix: don't return -ENONET in cec_receive()
[media] sir_ir: infinite loop in interrupt handler
[media] cec-notifier.h: handle unreachable CONFIG_CEC_CORE
[media] cec: improve MEDIA_CEC_RC dependencies
[media] vb2: Fix an off by one error in 'vb2_plane_vaddr'
[media] rainshadow-cec: Fix missing spin_lock_init()
[media] tc358743: fix register i2c_rd/wr function fix
Avoid that the following complaint is reported:
BUG: sleeping function called from invalid context at kernel/workqueue.c:2790
in_atomic(): 1, irqs_disabled(): 0, pid: 41, name: rcuop/3
1 lock held by rcuop/3/41:
#0: (rcu_callback){......}, at: [<ffffffff8111f9a2>] rcu_nocb_kthread+0x282/0x500
Call Trace:
dump_stack+0x86/0xcf
___might_sleep+0x174/0x260
__might_sleep+0x4a/0x80
flush_work+0x7e/0x2e0
__cancel_work_timer+0x143/0x1c0
cancel_work_sync+0x10/0x20
blk_throtl_exit+0x25/0x60
blkcg_exit_queue+0x35/0x40
blk_release_queue+0x42/0x130
kobject_put+0xa9/0x190
This happens since we invoke callbacks that need to block from the
queue release handler. Fix this by pushing the final release to
a workqueue.
Reported-by: Ross Zwisler <zwisler@gmail.com>
Fixes: commit b425e50492 ("block: Avoid that blk_exit_rl() triggers a use-after-free")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Updated changelog
Signed-off-by: Jens Axboe <axboe@fb.com>
Update ->ndo_change_mtu() callback comment to remove text
about returning error in case of undefined callback. This
change makes the comment match the existing code behavior.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
The macro CLOCKSOURCE_OF_DECLARE has been rename to TIMER_OF_DECLARE.
In order to prevent conflicts for the next merge window, a temporary
alias has been added which will be removed later.
Cc: Arnd Bergman <arnd@arndb.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
The config option name is now renamed to 'TIMER_OF' for consistency with
the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
The table name is now renamed to 'timer' for consistency with
the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
The macro name is now renamed to 'TIMER_ACPI_DECLARE' for consistency
with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the
clocksource at early stage. However, this macro is also used to initialize
the clockevent if any, or the clockevent only.
It was originally suggested to declare another macro to initialize a
clockevent, so in order to separate the two entities even they belong to the
same IP. This was not accepted because of the impact on the DT where splitting
a clocksource/clockevent definition does not make sense as it is a Linux
concept not a hardware description.
On the other side, the clocksource has not interrupt declared while the
clockevent has, so it is easy from the driver to know if the description is
for a clockevent or a clocksource, IOW it could be implemented at the driver
level.
So instead of dealing with a named clocksource macro, let's use a more generic
one: TIMER_OF_DECLARE.
The patch has not functional changes.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Turn restart_block.nanosleep.{rmtp,compat_rmtp} into a tagged union (kind =
1 -> native, kind = 2 -> compat, kind = 0 -> nothing) and make the places
doing actual copyout handle compat as well as native (that will become a
helper in the next commit). Result: compat wrappers, messing with
reassignments, etc. are gone.
[ tglx: Folded in a variant of Peter Zijlstras enum patch ]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-6-viro@ZenIV.linux.org.uk
Considering this case:
1. A program opens a sysfs table file 65535 times, it can increase
validation_count and first increment cause the table to be mapped:
validation_count = 65535
2. AML execution causes "Load" to be executed on the same
table, this time it cannot increase validation_count, so
validation_count remains:
validation_count = 65535
3. The program closes sysfs table file 65535 times, it can decrease
validation_count and the last decrement cause the table to be
unmapped:
validation_count = 0
4. AML code still accessing the loaded table, kernel crash can be
observed.
To prevent that from happening, add a validation_count threashold.
When it is reached, the validation_count can no longer be
incremented/decremented to invalidate the table descriptor (means
preventing table unmappings)
Note that code added in acpi_tb_put_table() is actually a no-op but
changes the warning message into a "warn once" one. Lv Zheng.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[ rjw: Changelog, comments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull key subsystem fixes from James Morris:
"Here are a bunch of fixes for Linux keyrings, including:
- Fix up the refcount handling now that key structs use the
refcount_t type and the refcount_t ops don't allow a 0->1
transition.
- Fix a potential NULL deref after error in x509_cert_parse().
- Don't put data for the crypto algorithms to use on the stack.
- Fix the handling of a null payload being passed to add_key().
- Fix incorrect cleanup an uninitialised key_preparsed_payload in
key_update().
- Explicit sanitisation of potentially secure data before freeing.
- Fixes for the Diffie-Helman code"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits)
KEYS: fix refcount_inc() on zero
KEYS: Convert KEYCTL_DH_COMPUTE to use the crypto KPP API
crypto : asymmetric_keys : verify_pefile:zero memory content before freeing
KEYS: DH: add __user annotations to keyctl_kdf_params
KEYS: DH: ensure the KDF counter is properly aligned
KEYS: DH: don't feed uninitialized "otherinfo" into KDF
KEYS: DH: forbid using digest_null as the KDF hash
KEYS: sanitize key structs before freeing
KEYS: trusted: sanitize all key material
KEYS: encrypted: sanitize all key material
KEYS: user_defined: sanitize key payloads
KEYS: sanitize add_key() and keyctl() key payloads
KEYS: fix freeing uninitialized memory in key_update()
KEYS: fix dereferencing NULL payload with nonzero length
KEYS: encrypted: use constant-time HMAC comparison
KEYS: encrypted: fix race causing incorrect HMAC calculations
KEYS: encrypted: fix buffer overread in valid_master_desc()
KEYS: encrypted: avoid encrypting/decrypting stack buffers
KEYS: put keyring if install_session_keyring_to_cred() fails
KEYS: Delete an error message for a failed memory allocation in get_derived_key()
...
Commit abb2ea7dfd ("compiler, clang: suppress warning for unused
static inline functions") just caused more warnings due to re-defining
the 'inline' macro.
So undef it before re-defining it, and also add the 'notrace' attribute
like the gcc version that this is overriding does.
Maybe this makes clang happier.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull ext4 fixes from Ted Ts'o:
"Fix various bug fixes in ext4 caused by races and memory allocation
failures"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix fdatasync(2) after extent manipulation operations
ext4: fix data corruption for mmap writes
ext4: fix data corruption with EXT4_GET_BLOCKS_ZERO
ext4: fix quota charging for shared xattr blocks
ext4: remove redundant check for encrypted file on dio write path
ext4: remove unused d_name argument from ext4_search_dir() et al.
ext4: fix off-by-one error when writing back pages before dio read
ext4: fix off-by-one on max nr_pages in ext4_find_unwritten_pgoff()
ext4: keep existing extra fields when inode expands
ext4: handle the rest of ext4_mb_load_buddy() ENOMEM errors
ext4: fix off-by-in in loop termination in ext4_find_unwritten_pgoff()
ext4: fix SEEK_HOLE
jbd2: preserve original nofs flag during journal restart
ext4: clear lockdep subtype for quota files on quota off
Pull RCU fixes from Ingo Molnar:
"Fix an SRCU bug affecting KVM IRQ injection"
* 'rcu-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
srcu: Allow use of Classic SRCU from both process and interrupt context
srcu: Allow use of Tiny/Tree SRCU from both process and interrupt context
Pull IOMMU fixes from Joerg Roedel:
- another compile-fix for my header cleanup
- a couple of fixes for the recently merged IOMMU probe deferal code
- fixes for ACPI/IORT code necessary with IOMMU probe deferal
* tag 'iommu-fixes-v4.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
arm: dma-mapping: Reset the device's dma_ops
ACPI/IORT: Move the check to get iommu_ops from translated fwspec
ARM: dma-mapping: Don't tear down third-party mappings
ACPI/IORT: Ignore all errors except EPROBE_DEFER
iommu/of: Ignore all errors except EPROBE_DEFER
iommu/of: Fix check for returning EPROBE_DEFER
iommu/dma: Fix function declaration
Pull block fixes from Jens Axboe:
"A set of fixes in the area of block IO, that should go into the next
-rc release. This contains:
- An OOPS fix from Dmitry, fixing a regression with the bio integrity
code in this series.
- Fix truncation of elevator io context cache name, from Eric
Biggers.
- NVMe pull from Christoph includes FC fixes from James, APST
fixes/tweaks from Kai-Heng, removal fix from Rakesh, and an RDMA
fix from Sagi.
- Two tweaks for the block throttling code. One from Joseph Qi,
fixing an oops from the timer code, and one from Shaohua, improving
the behavior on rotatonal storage.
- Two blk-mq fixes from Ming, fixing corner cases with the direct
issue code.
- Locking fix for bfq cgroups from Paolo"
* 'for-linus' of git://git.kernel.dk/linux-block:
block, bfq: access and cache blkg data only when safe
Fix loop device flush before configure v3
blk-throttle: set default latency baseline for harddisk
blk-throttle: fix NULL pointer dereference in throtl_schedule_pending_timer
nvme: relax APST default max latency to 100ms
nvme: only consider exit latency when choosing useful non-op power states
nvme-fc: fix missing put reference on controller create failure
nvme-fc: on lldd/transport io error, terminate association
nvme-rdma: fast fail incoming requests while we reconnect
nvme-pci: fix multiple ctrl removal scheduling
nvme: fix hang in remove path
elevator: fix truncation of icq_cache_name
blk-mq: fix direct issue
blk-mq: pass correct hctx to blk_mq_try_issue_directly
bio-integrity: Do not allocate integrity context for bio w/o data
Pull RCU fix from Paul E. McKenney:
" This series enables srcu_read_lock() and srcu_read_unlock() to be used from
interrupt handlers, which fixes a bug in KVM's use of SRCU in delivery
of interrupts to guest OSes. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While a 'struct key' itself normally does not contain sensitive
information, Documentation/security/keys.txt actually encourages this:
"Having a payload is not required; and the payload can, in fact,
just be a value stored in the struct key itself."
In case someone has taken this advice, or will take this advice in the
future, zero the key structure before freeing it. We might as well, and
as a bonus this could make it a bit more difficult for an adversary to
determine which keys have recently been in use.
This is safe because the key_jar cache does not use a constructor.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Pull power management fixes from Rafael Wysocki:
"These revert one problematic commit related to system sleep and fix
one recent intel_pstate regression.
Specifics:
- Revert a recent commit that attempted to avoid spurious wakeups
from suspend-to-idle via ACPI SCI, but introduced regressions on
some systems (Rafael Wysocki).
We will get back to the problem it tried to address in the next
cycle.
- Fix a possible division by 0 during intel_pstate initialization
due to a missing check (Rafael Wysocki)"
* tag 'pm-4.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle"
cpufreq: intel_pstate: Avoid division by 0 in min_perf_pct_min()
Each time a new speed is added, the bonding 802.3ad isn't updated. Add a
comment to remind the developer to update this driver.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The first netlink attribute (value 0) must always be defined
as none/unspec.
Because we cannot change an existing UAPI, I add a comment to point the
mistake and avoid to propagate it in a new ovs API in the future.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix messages like this:
adv7842.c:(.text+0x2edadd): undefined reference to `cec_unregister_adapter'
when CEC_CORE=m but the driver including media/cec.h is built-in. In that case
the static inlines provided in media/cec.h should be used by that driver.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Linu Cherian reported a WARN in cleanup_srcu_struct() when shutting
down a guest running iperf on a VFIO assigned device. This happens
because irqfd_wakeup() calls srcu_read_lock(&kvm->irq_srcu) in interrupt
context, while a worker thread does the same inside kvm_set_irq(). If the
interrupt happens while the worker thread is executing __srcu_read_lock(),
updates to the Classic SRCU ->lock_count[] field or the Tree SRCU
->srcu_lock_count[] field can be lost.
The docs say you are not supposed to call srcu_read_lock() and
srcu_read_unlock() from irq context, but KVM interrupt injection happens
from (host) interrupt context and it would be nice if SRCU supported the
use case. KVM is using SRCU here not really for the "sleepable" part,
but rather due to its IPI-free fast detection of grace periods. It is
therefore not desirable to switch back to RCU, which would effectively
revert commit 719d93cd5f ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING",
2014-01-16).
However, the docs are overly conservative. You can have an SRCU instance
only has users in irq context, and you can mix process and irq context
as long as process context users disable interrupts. In addition,
__srcu_read_unlock() actually uses this_cpu_dec() on both Tree SRCU and
Classic SRCU. For those two implementations, only srcu_read_lock()
is unsafe.
When Classic SRCU's __srcu_read_unlock() was changed to use this_cpu_dec(),
in commit 5a41344a3d ("srcu: Simplify __srcu_read_unlock() via
this_cpu_dec()", 2012-11-29), __srcu_read_lock() did two increments.
Therefore it kept __this_cpu_inc(), with preempt_disable/enable in
the caller. Tree SRCU however only does one increment, so on most
architectures it is more efficient for __srcu_read_lock() to use
this_cpu_inc(), and any performance differences appear to be down in
the noise.
Cc: stable@vger.kernel.org
Fixes: 719d93cd5f ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING")
Reported-by: Linu Cherian <linuc.decode@gmail.com>
Suggested-by: Linu Cherian <linuc.decode@gmail.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
